High performance integrated circuits are driving the demand for high performance sockets, such as those disclosed herein and in U.S. Pat. Nos. 6,247,938; 6,409,521; 6,939,143; 6,957,963; 6,830,460; 7,114,960; 7,121,839; and 7,160,119, which are hereby incorporated by reference. As bus architectures become increasingly complex the frequency of the signals is much higher and more sensitive to changes in impedance. Next generation systems are running at about 5 GHz. High performance sockets, such as those identified above, have decreased pin pitch from about 1 millimeter (“mm”) to from between about 0.4 mm and about 0.5 mm and pin count is increasing.